CN1754310A

CN1754310A - Data transmission method, base station and transmitter

Info

Publication number: CN1754310A
Application number: CN200480004865.XA
Authority: CN
Inventors: 米拉·卡加雷宁; 萨姆·萨阿里宁; 考柯·黑尼克斯基; 蒂姆·托罗宁; 朱哈·伊丽宁; 佳尼·索恩皮拉; 里斯托·利蒂宁
Original assignee: Nokia Inc
Current assignee: Nokia Solutions and Networks Oy
Priority date: 2003-02-27
Filing date: 2004-02-26
Publication date: 2006-03-29
Also published as: US20060141955A1; US7197287B2; EP1597822B1; US20040171358A1; EP1597822A1; ATE392043T1; WO2004077660A1; DE602004012976D1; DE602004012976T2; US7035601B2; JP2006518123A

Abstract

The transmitter compensates for non-linearities within the transmission chain. The transmitter comprises first forming means for forming at least one state expansion vector comprising quantities characterizing a signal, based on at least one set of signal properties. The transmitter comprises modifying means for modifying the signal characterizing quantities of the at least one state expansion vector with the at least one time-domain compensation parameter vector and with the at least one frequency-domain compensation parameter vector, thereby forming a pre-distorted signal. The transmitter comprises a second forming means for forming a feedback signal from the output signal of the transmission chain of the modified signal. The transmitter includes an adapter that adapts at least one time-domain compensation parameter vector based on a residual error between the transmit signal and the feedback signal, and that adapts at least one frequency-domain compensation parameter vector.

Description

Data transmission method, base station and reflector

Technical field

The present invention relates to data transmission method, base station and reflector in the communication system.

Background technology

In radio communications system, before transmitting, the required power amplifier comes amplifying signal, because radio communication number decays on radio path.Unfortunately, the high power RF amplifier is non-linear equipment often, so in many cases, they cause distortion.This distortion is expressed as the out-of-band power in for example intersymbol interference or the nearby frequency bands.ACLR (adjacent carrier leak rate) quantizes the outer emitted power of band, thereby it must remain in the limit of regulation.

In the prior art, the nonlinear several distinct methods that have compensating power amplifier.The compensation of non-linearity of power amplifier can be divided into three kinds of primary categories: feedback, feedforward and predistortion.Predistortion often is called as preemphasis.

Feedback technique mainly is used in the audio frequency amplifier.But, because the real-time cause that realizes of feedback circuit, to the FEEDBACK CONTROL of the radio frequency difficulty that becomes.Linearizing Multi-Carrier Power Amplifier has been proposed in addition.It uses cartesian feedback.This technology is not suitable for broadband emitters, because its frequency band is narrower.

With regard to broadband application, for example linearisation of WCDMA (Wideband Code Division Multiple Access (WCDMA)), the main feed-forward technique that uses in the prior art.In feed-forward amplifier, detect distortion or the error signal that in amplifier, produces by comparator input signal and output signal.The error signal that detects is admitted in the linear sub amplifier, so that they are amplified to the level identical with power amplifier.From the output of power amplifier, deduct the error signal of amplification subsequently.Problem is that the linearity of sub-amplifier must be higher, and this can reduce total power efficiency.

In the predistorter amplifier, predistorter adds pre-distorted signals in advance in input signal, so that eliminate the distortion that produces in amplifier.Problem is if amplifier parameter drift-out design load, and compensation performance worsens so.

Exist and make the adaptive existing solution of predistorter amplifier.But the problem of this existing solution is that the linearisation of distorted signal is inadequate.In general, pre-distortion parameters is stored in the tracing table, but this method is easy to enlarge memory size, and produces quantizing noise, because parameter generally differs predetermined step-length each other.

Summary of the invention

An object of the present invention is to provide a kind of compensation by the non-linear equipment in the chain, the improving one's methods of the distortion that causes such as power amplifier.According to one embodiment of present invention, provide a kind of nonlinear data transmission method that compensates chain, described method comprises: at first form at least one time domain compensation parameter vector; Next forms at least one frequency domain compensation parameter vector; Determine the nonlinear at least one group of characteristics of signals in the analogue transmission chain; The 3rd, according to described at least one group of characteristics of signals, form at least one state spread vector of the value that comprises characterization signal; Revise the characterization value of at least one state spread vector with described at least one time domain compensation parameter vector and described at least one frequency domain compensation parameter vector, thereby form pre-distorted signals; The 4th, form feedback signal by the output signal of chain; At first according to transmit and feedback signal between residual error, revise described at least one time domain compensation parameter vector; And next according to transmit and feedback signal between residual error, revise described at least one frequency domain compensation parameter vector.

The invention still further relates to a kind of nonlinear data transmission method that compensates chain, described method comprises: at first form at least one time domain compensation parameter vector; Next forms at least one frequency domain compensation parameter vector; Determine the nonlinear at least one group of characteristics of signals in the analogue transmission chain; The 3rd, according to described at least one group of characteristics of signals, form at least one state spread vector of the value that comprises characterization signal; Revise the characterization value of at least one state spread vector with described at least one time domain compensation parameter vector and described at least one frequency domain compensation parameter vector, thereby form pre-distorted signals; The 4th, form feedback signal by the output signal of chain; Filter feedback signal, make the non-linear frequency response of feedback link reduce to minimum; At first according to transmit and feedback signal between residual error, revise described at least one time domain compensation parameter vector; Secondly according to transmit and feedback signal between residual error, revise described at least one frequency domain compensation parameter vector; With the 3rd, according to transmit and feedback signal between residual error, revise at least one compensation parameter vector of described feedback filter.

According to one embodiment of present invention, provide a kind of nonlinear data transmission method that compensates chain, described method comprises: at first form at least one time domain compensation parameter vector; Next forms at least one frequency domain compensation parameter vector; The 3rd, form at least one quadrature modulator compensation parameter vector; Determine the nonlinear at least one group of characteristics of signals in the analogue transmission chain; The 4th, according to described at least one group of characteristics of signals, form at least one state spread vector of the value that comprises characterization signal; Revise the characterization value of at least one state spread vector with described at least one time domain compensation parameter vector, described at least one frequency domain compensation parameter vector and described at least one quadrature modulator compensation parameter vector, thereby form pre-distorted signals; The 5th, form feedback signal by the output signal of chain; At first according to transmit and feedback signal between residual error, revise described at least one time domain compensation parameter vector; Secondly according to transmit and feedback signal between residual error, revise described at least one frequency domain compensation parameter vector; With the 3rd, according to transmit and feedback signal between residual error, revise described at least one quadrature modulator compensation parameter vector.

According to one embodiment of present invention, provide a kind of nonlinear data transmission method that compensates chain, described method comprises: at first form at least one time domain compensation parameter vector; Next forms at least one frequency domain compensation parameter vector; The 3rd, form at least one quadrature modulator compensation parameter vector; Determine the nonlinear at least one group of characteristics of signals in the analogue transmission chain; The 4th, according to described at least one group of characteristics of signals, form at least one state spread vector of the value that comprises characterization signal; Revise the characterization value of at least one state spread vector with described at least one time domain compensation parameter vector, described at least one frequency domain compensation parameter vector and described at least one quadrature modulator compensation parameter vector, thereby form pre-distorted signals; The 5th, form feedback signal by the output signal of chain; Filter feedback signal, make the non-linear frequency response of feedback link reduce to minimum; At first according to transmit and feedback signal between residual error, revise described at least one time domain compensation parameter vector; Secondly according to transmit and feedback signal between residual error, revise described at least one frequency domain compensation parameter vector; The 3rd, according to transmit and feedback signal between residual error, revise described at least one quadrature modulator compensation parameter vector; With the 4th, according to transmit and feedback signal between residual error, revise at least one compensation parameter vector of feedback filter.

The present invention relates to compensate the nonlinear reflector of chain, described reflector comprises: form first of at least one time domain compensation parameter vector and form device; Form second of at least one frequency domain compensation parameter vector and form device; Determine definite device of the nonlinear at least one group of characteristics of signals in the analogue transmission chain; According to described at least one group of characteristics of signals, form the 3rd formation device of at least one state spread vector of the value that comprises characterization signal; Revise the characterization value of at least one state spread vector with described at least one time domain compensation parameter vector and described at least one frequency domain compensation parameter vector, thereby form the modifier of pre-distorted signals; Form the 4th of feedback signal by the output signal of chain and form device; According to transmit and feedback signal between residual error, first self-reacting device of adaptive described at least one time domain compensation parameter vector; And according to transmit and feedback signal between residual error, second self-reacting device of adaptive described at least one frequency domain compensation parameter vector.

The invention still further relates to a kind of nonlinear reflector that compensates chain, described reflector comprises: form first of at least one time domain compensation parameter vector and form device; Form second of at least one frequency domain compensation parameter vector and form device; Determine definite device of the nonlinear at least one group of characteristics of signals in the analogue transmission chain; According to described at least one group of characteristics of signals, form the 3rd formation device of at least one state spread vector of the value that comprises characterization signal; Revise the characterization value of at least one state spread vector with described at least one time domain compensation parameter vector and described at least one frequency domain compensation parameter vector, thereby form the modifier of pre-distorted signals; Form the 4th of feedback signal by the output signal of chain and form device; Filter feedback signal, make the non-linear frequency response of feedback link reduce to minimum filter; According to transmit and feedback signal between residual error, first self-reacting device of adaptive described at least one time domain compensation parameter vector; According to transmit and feedback signal between residual error, second self-reacting device of adaptive described at least one frequency domain compensation parameter vector; And according to transmit and feedback signal between residual error, the 3rd self-reacting device of at least one compensation parameter vector of adaptive feedback filter.

The invention still further relates to a kind of nonlinear reflector that compensates chain, described reflector comprises: form first of at least one time domain compensation parameter vector and form device; Form second of at least one frequency domain compensation parameter vector and form device; Form the 3rd of at least one quadrature modulator compensation parameter vector and form device; Determine definite device of the nonlinear at least one group of characteristics of signals in the analogue transmission chain; According to described at least one group of characteristics of signals, form the 4th formation device of at least one state spread vector of the value that comprises characterization signal; Revise the characterization value of at least one state spread vector with described at least one time domain compensation parameter vector, described at least one frequency domain compensation parameter vector and described at least one quadrature modulator compensation parameter vector, thereby form the modifier of pre-distorted signals; Form the 5th of feedback signal by the output signal of chain and form device; According to transmit and feedback signal between residual error, first self-reacting device of adaptive described at least one time domain compensation parameter vector; According to transmit and feedback signal between residual error, second self-reacting device of adaptive described at least one frequency domain compensation parameter vector; And according to transmit and feedback signal between residual error, the 3rd self-reacting device of adaptive described at least one quadrature modulator compensation parameter vector.

The invention still further relates to a kind of nonlinear reflector that compensates chain, described reflector comprises: form first of at least one time domain compensation parameter vector and form device; Form second of at least one frequency domain compensation parameter vector and form device; Form the 3rd of at least one quadrature modulator compensation parameter vector and form device; Determine definite device of the nonlinear at least one group of characteristics of signals in the analogue transmission chain; According to described at least one group of characteristics of signals, form the 4th formation device of at least one state spread vector of the value that comprises characterization signal; Revise the characterization value of at least one state spread vector with described at least one time domain compensation parameter vector, described at least one frequency domain compensation parameter vector and described at least one quadrature modulator compensation parameter vector, thereby form the modifier of pre-distorted signals; Form the 5th of feedback signal by the output signal of chain and form device; Filter feedback signal, make the non-linear frequency response of feedback link reduce to minimum filter; According to transmit and feedback signal between residual error, first self-reacting device of adaptive described at least one time domain compensation parameter vector; According to transmit and feedback signal between residual error, second self-reacting device of adaptive described at least one frequency domain compensation parameter vector; According to transmit and feedback signal between residual error, the 3rd self-reacting device of adaptive described at least one quadrature modulator compensation parameter vector; And according to transmit and feedback signal between residual error, the four selfs adaptive device of at least one compensation parameter vector of adaptive feedback filter.

The invention still further relates to the nonlinear reflector of compensation chain, described reflector is configured to: form at least one time domain compensation parameter vector; Form at least one frequency domain compensation parameter vector; Form at least one quadrature modulator compensation parameter vector; Determine the nonlinear at least one group of characteristics of signals in the analogue transmission chain; According to described at least one group of characteristics of signals, form at least one state spread vector of the value that comprises characterization signal; With described at least one time domain compensation parameter vector, described at least one frequency domain compensation parameter vector and described at least one quadrature modulator compensation parameter vector are revised the characterization value of at least one state spread vector, thereby form pre-distorted signals; Output signal by chain forms feedback signal; According to transmit and feedback signal between residual error, adaptive described at least one time domain compensation parameter vector; According to transmit and feedback signal between residual error, adaptive described at least one frequency domain compensation parameter vector; And according to transmit and feedback signal between residual error, adaptive described at least one quadrature modulator compensation parameter vector.

The invention still further relates to a kind of nonlinear reflector that compensates chain, described reflector is configured to: form at least one time domain compensation parameter vector; Form at least one frequency domain compensation parameter vector; Determine the nonlinear at least one group of characteristics of signals in the analogue transmission chain; According to described at least one group of characteristics of signals, form at least one state spread vector of the value that comprises characterization signal; Revise the characterization value of at least one state spread vector with described at least one time domain compensation parameter vector and described at least one frequency domain compensation parameter vector, thereby form pre-distorted signals; Output signal by chain forms feedback signal; Filter feedback signal, make the non-linear frequency response of feedback link reduce to minimum; According to transmit and feedback signal between residual error, adaptive described at least one time domain compensation parameter vector; According to transmit and feedback signal between residual error, adaptive described at least one frequency domain compensation parameter vector; And according to transmit and feedback signal between residual error, at least one coefficient of adaptive feedback filter.

The invention still further relates to a kind of nonlinear reflector that compensates chain, described reflector is configured to: form at least one time domain compensation parameter vector; Form at least one frequency domain compensation parameter vector; Form at least one quadrature modulator compensation parameter vector; Determine the nonlinear at least one group of characteristics of signals in the analogue transmission chain; According to described at least one group of characteristics of signals, form at least one state spread vector of the value that comprises characterization signal; Revise the characterization value of at least one state spread vector with described at least one time domain compensation parameter vector, described at least one frequency domain compensation parameter vector and described at least one quadrature modulator compensation parameter vector, thereby form pre-distorted signals; Output signal by chain forms feedback signal; According to transmit and feedback signal between residual error, adaptive described at least one time domain compensation parameter vector; According to transmit and feedback signal between residual error, adaptive described at least one frequency domain compensation parameter vector; And according to transmit and feedback signal between residual error, adaptive described at least one quadrature modulator compensation parameter vector.

The invention still further relates to a kind of nonlinear reflector that compensates chain, described reflector is configured to: form at least one time domain compensation parameter vector; Form at least one frequency domain compensation parameter vector; Form at least one quadrature modulator compensation parameter vector; Determine the nonlinear at least one group of characteristics of signals in the analogue transmission chain; According to described at least one group of characteristics of signals, form at least one state spread vector of the value that comprises characterization signal; Revise the characterization value of at least one state spread vector with described at least one time domain compensation parameter vector, described at least one frequency domain compensation parameter vector and described at least one quadrature modulator compensation parameter vector, thereby form pre-distorted signals; Output signal by chain forms feedback signal; Filter feedback signal, make the non-linear frequency response of feedback link reduce to minimum; According to transmit and feedback signal between residual error, adaptive described at least one time domain compensation parameter vector; According to transmit and feedback signal between residual error, adaptive described at least one frequency domain compensation parameter vector; According to transmit and feedback signal between residual error, adaptive described at least one quadrature modulator compensation parameter vector; And according to transmit and feedback signal between residual error, at least one coefficient of adaptive feedback filter.

The invention still further relates to a kind of base station, wherein the non-linear of chain compensated, and described base station comprises: form first of at least one time domain compensation parameter vector and form device; Form second of at least one frequency domain compensation parameter vector and form device; Determine definite device of the nonlinear at least one group of characteristics of signals in the analogue transmission chain; According to described at least one group of characteristics of signals, form the 3rd formation device of at least one state spread vector of the value that comprises characterization signal; Revise the characterization value of at least one state spread vector with described at least one time domain compensation parameter vector and described at least one frequency domain compensation parameter vector, thereby form the modifier of pre-distorted signals; Form the 4th of feedback signal by the output signal of chain and form device; According to transmit and feedback signal between residual error, first self-reacting device of adaptive described at least one time domain compensation parameter vector; And according to transmit and feedback signal between residual error, second self-reacting device of adaptive described at least one frequency domain compensation parameter vector.

The invention still further relates to a kind of base station, wherein the non-linear of chain compensated, and described base station comprises: form first of at least one time domain compensation parameter vector and form device; Form second of at least one frequency domain compensation parameter vector and form device; Form the 3rd of at least one quadrature modulator compensation parameter vector and form device; Determine definite device of the nonlinear at least one group of characteristics of signals in the analogue transmission chain; According to described at least one group of characteristics of signals, form the 4th formation device of at least one state spread vector of the value that comprises characterization signal; With described at least one time domain compensation parameter vector, described at least one frequency domain compensation parameter vector and described at least one quadrature modulator compensation parameter vector are revised the characterization value of at least one state spread vector, thereby form the modifier of pre-distorted signals; Form the 5th of feedback signal by the output signal of chain and form device; According to transmit and feedback signal between residual error, first self-reacting device of adaptive described at least one time domain compensation parameter vector; According to transmit and feedback signal between residual error, second self-reacting device of adaptive described at least one frequency domain compensation parameter vector; And according to transmit and feedback signal between residual error, the 3rd self-reacting device of adaptive described at least one quadrature modulator compensation parameter vector.

The invention still further relates to a kind of base station, wherein the non-linear of chain compensated, and described base station comprises: form first of at least one time domain compensation parameter vector and form device; Form second of at least one frequency domain compensation parameter vector and form device; Determine definite device of the nonlinear at least one group of characteristics of signals in the analogue transmission chain; According to described at least one group of characteristics of signals, form the 3rd formation device of at least one state spread vector of the value that comprises characterization signal; Revise the characterization value with described at least one time domain compensation parameter vector and described at least one frequency domain compensation parameter vector, thereby form the modifier of pre-distorted signals; Form the 4th of feedback signal by the output signal of chain and form device; Filter feedback signal, make the non-linear frequency response of feedback link reduce to minimum filter; According to transmit and feedback signal between residual error, first self-reacting device of adaptive described at least one time domain compensation parameter vector; According to transmit and feedback signal between residual error, second self-reacting device of adaptive described at least one frequency domain compensation parameter vector; And according to transmit and feedback signal between residual error, the 3rd self-reacting device of at least one compensation parameter vector of adaptive feedback filter.

The invention still further relates to a kind of base station, wherein the non-linear of chain compensated, and described base station comprises: form first of at least one time domain compensation parameter vector and form device; Form second of at least one frequency domain compensation parameter vector and form device; Form the 3rd of at least one quadrature modulator compensation parameter vector and form device; Determine definite device of the nonlinear at least one group of characteristics of signals in the analogue transmission chain; According to described at least one group of characteristics of signals, form the 4th formation device of at least one state spread vector of the value that comprises characterization signal; With described at least one time domain compensation parameter vector, described at least one frequency domain compensation parameter vector and described at least one quadrature modulator compensation parameter vector are revised the characterization value of at least one state spread vector, thereby form the modifier of pre-distorted signals; Form the 5th of feedback signal by the output signal of chain and form device; Filter feedback signal, make the non-linear frequency response of feedback link reduce to minimum filter; According to transmit and feedback signal between residual error, first self-reacting device of adaptive described at least one time domain compensation parameter vector; According to transmit and feedback signal between residual error, second self-reacting device of adaptive described at least one frequency domain compensation parameter vector; According to transmit and feedback signal between residual error, the 3rd self-reacting device of adaptive described at least one quadrature modulator compensation parameter vector; And according to transmit and feedback signal between residual error, the four selfs adaptive device of at least one coefficient of adaptive feedback filter.

In addition, another preferred embodiment of the present invention has further improved linearisation, because the frequency domain distortion that appears at usually in the analog circuit is also compensated.

Description of drawings

Below, with reference to preferred embodiments and drawings, illustrate in greater detail the present invention, wherein:

Fig. 1 represents the simplified example of communication system according to an embodiment of the invention;

Fig. 2 is according to one embodiment of present invention, the flow chart of the non-linear method of compensation chain;

Fig. 3 A-B is according to another embodiment of the present invention, another flow chart of the non-linear method of compensation chain;

Fig. 4 is the block diagram of the part of reflector according to an embodiment of the invention;

Fig. 5 has represented the example of base station transceiver according to an embodiment of the invention.

Embodiment

With reference to figure 1, Fig. 1 has represented to use an example of the data transmission system of preferential embodiment of the present invention.Among Fig. 1, describe this embodiment in the radio system of simplifying, the radio system typical example of described simplification is as, code division multiple access (CDMA) system.CDMA (Code Division Multiple Access) is used in the radio system that for example is called as IMT-2000 (international system communication 2000) and UMTS (general-purpose system communication system) at least at present.But, these systems that this embodiment is not limited to provide as an example, those skilled in the art can be applied to this solution possess other radio system of essential attributes.

Fig. 1 describes the most important network elements of radio system and the simplified block diagram of the interface between them.Because the 26S Proteasome Structure and Function of network components is generally known, therefore be not described in detail.

The major part of radio system is a core network (CN) 100, radio access network 130 and subscriber equipment (UE) 170.Term UTRAN is a UMTS terrestrial radio access network, promptly belongs to the third generation and the abbreviation of the radio access network realized by Wideband Code Division Multiple Access (WCDMA) (WCDMA).In general, radio system also can by as give a definition: (it comprises the fixed infrastructure of radio system to radio system by user terminal (it is also referred to as subscriber's terminal or mobile radio station) and network portion, be core network, radio access network and base station system) form.

Move switching center (MSC) the 102nd, the center of the circuit switched side of core network 100 served.Move and serve the connection that switching center 102 is used to serve as radio access network 130.Mobile task of serving switching center 102 generally comprises collection, data encryption parameter management, frequency allocation management and the echo of exchange, paging, user terminal location registration, handover management, subscriber's accounting information and eliminates.

Move the number could vary of serving switching center 102.For example, little network operator may only have one and move and to serve switching center 102, and big core network 100 may have several moving and serves switching centers 102.Fig. 1 represented that another moves and served switching center 106, but in order to make Fig. 1 sufficiently clear, do not have graphic extension its with being connected of other network components.

Big core network 100 can comprise that independently gateway that the circuit switched be responsible between core network 100 and the external network 180 connects moves and serve switching center (GMSC) 110.Gateway moves serves switching center 110 and serves between switching center 102,106 and the external network 180 moving.External network 180 can be, for example Public Land Mobile Nerwork PLMN or public switch telephone network PSTN.

Core network 100 generally also comprises other parts, for example Home Location Register (HLR) and visitor location register (VLR), Home Location Register (HLR) comprises permanent subscriber register, and packet data protocol (PDP) address (if radio system is supported GPRS), visitor location register (VLR) comprises and the roaming relevant information of user terminal 170 in moving the zone of serving switching center 102.In order to make Fig. 1 clear, do not represent whole parts of core network among the figure.

Serving GPRS Support Node (SGSN) the 118th, the center of the packet switching side of core network 100.One of main task of Serving GPRS Support Node 118 is to utilize radio access network 130, transmits and receives grouping with respect to the user terminal 170 of supporting packet-switched transmission.Serving GPRS Support Node 118 comprises the positional information of user profile and user terminal 170.

Gateway GPRS support (GGSN) 120 of packet switching side moves corresponding to the gateway of circuit switched side and serves switching center 110, except Gateway GPRS Support Node 120 must send to the output communication from core network 100 external network 182, and gateway moves and serves 110 of switching centers and send outside the input communication.In this example, external network 182 represented by the internet, followingly can transmit quite most radiotelephone communication by the internet.

Radio access network 130 is made up of radio network sub-system 140,150.Each radio network sub-system 140,150 is made up of radio network controller (RNC) 146,156 and B node 142,144,152,154.Term B node representative " base station ".

Radio network controller 146,156 is responsible for following task usually, for example: the management of the radio resource of base station transceiver or B node 142,144,152,154, switch the minizone, the measurement of the time delay on the up link, the management of the realization of operation and management interface and power control.

Radio network controller 146,156 comprises at least one transceiver.A radio network controller 146,156 can be served a sub-district or several sector cell.Cell diameter can be from several meters to many kilometers.Radio network controller 146,156 usually is considered to also comprise code converter, is used for being implemented in the conversion between speech coding form that radio system uses and the speech coding form that uses in public switched telephone system.But in fact, code converter is usually located to move and serves in the switching center 102.Radio network controller 146,156 is responsible for following task usually, and for example: to the measurement of up link, chnnel coding is encrypted and the scrambling coding.

User terminal 170 is made up of two parts: mobile device (ME) 172 and UMTS subscriber identification module (USIM) 174.User terminal 170 comprises at least one transceiver, is used to set up the dedicated radio link with radio access network 130.User terminal 170 can comprise at least two different subscriber identification modules.In addition, user terminal 170 comprises antenna, user interface and battery.Various types of user terminals 170 be can obtain at present, terminal and portable terminal in the automobile for example are installed in.User terminal 170 also has and personal computer or the similar character of portable computer.

USIM 174 comprises user profile and about Information Security, especially the information of cryptographic algorithm.

To one skilled in the art, the interface that is included in the radio communications system is determined by the standard of hardware realization and use, so the interface of system can be different from those interfaces shown in Fig. 1.In UMTS, most important interface is the Iu interface between core network and the radio access network, it is divided into IuCS (CS=circuit switched) interface of circuit switched side and IuPS (PS=packet switching) interface of packet switching side, and the Uu interface between radio access network and the user terminal.Which kind of message the different network components of interface definition can use intercom mutually.The aims of standardization of interface are to make the operation between the network components of different manufacturers become possibility.But in fact, some interfaces are specific to manufacturer.

Fig. 2 represents according to the present invention, the flow chart of an embodiment of the method for realization digital pre-distortion or preemphasis.A purpose of this method is the non-linear of compensation chain.Briefly, general passing through adds pre-distorted signals to base band signal modulated, thereby compensation realizes linearisation in the WBD wideband distortion of the output of non-linear equipment.This method is particularly suitable for compensating the signal non-linear that is caused by the power amplifier in the reflector.

Power amplifier has three major requirements: high power output, high efficiency and low distortion.The design power amplifier generally is trading off between these require.Non-linear high-efficiency amplifier makes amplitude and all distortions of phase place of signal.Non-linear inter-modulation distortion and the spectral re-growth of also causing.These can cause adjacent-channel interference, because the cause of adjacent-channel interference, network performance worsens.The chain that comprises power amplifier is also introduced the non-linear frequency transfer function.On the other hand, linear amplifier efficient is low, and this causes feasibility to reduce, and cost increases, and the increase that produces.

For adjacent channel leakage power (ACP) being suppressed to the predeterminated level of determining by system specifications, generally need linearisation.Especially when using high transmit power, needs more to make in this way.

Should notice that in the method the most handy polar coordinate system of signal value is represented, because polar coordinate system generally provides result more accurately.It also makes the present invention can be with real number form rather than complex value processing signals.

This method starts from square frame 200.In square frame 202, form at least one time domain compensation parameter.Parameter vector can comprise one or more subvectors, and each subvector is relevant with the nonlinear signal specific characteristic that relates to power amplifier.

By providing its coefficient, parameter vector (function) is determined polynomial function, spline function or any other function.In this application, vector also means the matrix type vector.Batten can be characterized as being a function, and this function is the son multinomial at interval about every group of appointment in its territory.At son boundary at interval, batten is level and smooth equally.The time domain compensation parameter vector is used to the time domain predistortion.

Usually function (or vector) can be than using independent value to describe the complex effects that is caused by non-linear better, and main because of for the purpose of practicality, the size of memory (in the prior art, using tracing table) must be limited.Usually need several vectors, because the use of different vectors produces result more accurately.The number of the vector of selecting and vector itself depend on the typical radio electricity condition of system, and depend on required compensation precision naturally.Following four functions of general use: memoryless predistortion function, dynamically predistortion function, the dynamic predistortion function of weighted integral and the dynamic predistortion function of cross term.Difference between these functions can be interpreted into as described below.Memoryless predistortion function uses the range value of sampling, and dynamically the predistortion function also utilizes previous range value, so can predict the following direction that changes better.Integration predistortion function uses the review time cycle longer than dynamic predistortion function.By utilizing longer cycle review time, can follow the tracks of in the response of non-linear equipment, owing to the change of variations in temperature.The dynamic predistortion function of cross term utilizes memoryless function, kinematic function and integral function.It generally multiplies each other the value of these function definitions.In other words, by the output of making up other piece, form the cross term function according to suitable mode.

At square frame 204, form at least one frequency domain parameter vector (perhaps function).In theory, by transmission signals being used the inverse of nonlinear transfer function, can eliminate the infringement that causes by non-linear.But in fact, except the time domain error, always there is the frequency domain error, thereby also needs the frequency domain predistortion.Preferably transmit and feedback signal, and, form the frequency compensation parameter vector according to the results modification reverse filtration by analysis.

At square frame 206, form at least one quadrature modulator compensation parameter vector.At AQM (analogue quadrature moducator) and in AQDeMod (analog quadrature demodulator) compensation, the real part and the imaginary part of complex signal are adjusted, so that the error minimize that quadrature modulation or quadrature demodulation cause.General by in the predetermined sample of I (equally) and Q (quadrature) modulation signal, adding correction term, realize this compensation.General by the same historical information of using, obtain correction term from current I and Q sample.Usually (its independent variable is current and I in the past and Q sample (AQM state expander vector) and the previous AQM compensating parameter of determining, the calculation correction item according to predetermined function.In typical the realization, current and I in the past and Q sample and the function of the previous AQM compensating parameter of determining and the element linear correlation of predistorter coefficient and AQM state expander vector.For example, can use more complicated structure, wherein correction term is not relevant with described linear-in-the-parameter, but depends on described parameter with a kind of more complicated form.

AQM state expander vector has the various functions as the I of component and Q and their value formerly.Typical A QM state expander component is the product of the low order power (low power) of I and Q and their value formerly, and some aggregate functions of value formerly, for example in the fixed time, sample of signal square the integration of amplitude.Possible in-phase component and quadrature component all have their AQM state expander vector.Usually, the one-component of AQM state expander is constant.This is used to DC-skew (DC=direct current) compensation.

By using according to feedback signal and primary signal, make the maximized algorithm of predetermined optimal standards, can find the AQM compensating parameter.In general, optimal standards is the negative value maximum that makes the mean square deviation between primary signal and the one or more feedback signal.If the use linear model in self adaptation, can use the LMS (lowest mean square) or RLS (recursive least square) algorithm of prior art so.In the AQM self adaptation, little frequency displacement can be joined in the feedback link, thus the linearity error between separate modulator and the demodulator.

Also can realize AQDeMod (analog quadrature demodulator) compensation.In essence, can utilize identical method compensation AQDeMod and AQM, but in different self adaptation circulations (round), carry out described compensation independently usually: at first, carry out the AQM compensation, utilize residual error compensation AQDeMod subsequently.In the AQDeMod self adaptation, little frequency displacement can be joined in the feedback link equally, thus the linearity error between separate modulator and the demodulator.

In an embodiment of this method, do not carry out AQM (analogue quadrature moducator) and AQDeMod (analog quadrature demodulator) compensation.

At square frame 208, determine the nonlinear at least one group of characteristics of signals in the analogue transmission chain.In general, some character of the signal that uses among the present invention can comprise amplitude, phase place or frequency.In many cases, one group of characteristics of signals is just enough, but sometimes in order to obtain result more accurately, may need many group characteristics of signals.The non-linear of chain simulated, so that be identified for forming the parameter of state spread vector in square frame 210.

In square frame 210,, form at least one state spread vector according at least one group of characteristics of signals.The state spread vector is made up of the value that with non-linear sign is the function of the characteristics of signals selected.For example, the state spread vector can be by being arranged in vector, and the not homogeneous power of the predetermined number of range value forms.Another example is that the state spread vector is made up of the power of the time-derivative of the amplitude of predetermined number.Another example is the state spread vector by according to different modes: by difference, the range value that integration etc. are handled forms.The range value of handling according to different modes also capable of being combined.So the state spread vector can be by one or more range values, one or more derivative range values, one or more integration range values and/or the combined value that can be called as cross term constitute.

The number of variations of the item of the required type in the state spread vector:,, may need more eurypalynous still for more complicated situation sometimes by only using a kind of (for example amplitude) can obtain good result.The length of state spread vector depends on the requirement of predistortion.In other words, Xiang number depends on the required quality of predistortion.Sometimes, use short vector can obtain good result, but for more complicated situation, the length of vector can be increased.

According to frequency, bandwidth, power or another chain variable, can in the state expander, use different settings, and be that time domain is selected different compensating parameters with frequency domain predistortion and AQM compensation.

At square frame 212, utilize at least one time domain compensation parameter vector, utilize at least one frequency domain compensation parameter vector and at least one AQM compensation parameter vector to revise the characterization value, thereby form pre-distorted signals.Time domain is revised generally and to be characterized the selection parameter that value multiply by one or more time domain compensation parameter vectors by the prearranged signals with one or more state spread vector and realize.In general, the value that is multiplied each other is amplitude and/or phase parameter.In a preferred embodiment of the invention, in polar coordinate system, carry out the time domain predistortion.After time domain compensation, the parameter of compensation is combined so that obtain a value of each parameter, for example each raw value phase value and a range value.

Preferably, realize frequency domain compensation by filtering time domain preemphasized signal value.The compensating filter structure generally comprises one or more filters or filter set, is used for the non-linear of compensating frequency response.This distortion is compensated by filter.The relatively frequency response that is predefined for mirror image and the chain of this filter.Purpose is the frequency response linearityization that makes chain.In principle, can by relatively transmit and feedback signal between error, form the frequency response that the reverse filtration device comes balanced chain.In general, the behavior and the character of state expander control frequency domain predistortion.

If do not need frequency domain compensation, the filter taps coefficient can the value of being set to 1 so.

Generally characterize the selection parameter that value multiply by one or more AQM compensation parameter vectors and realize the AQM compensation by prearranged signals with one or more AQM state spread vector.

In a preferred embodiment of the invention, in cartesian coordinate system, realize the AQM compensation.

At square frame 214, feedback signal forms the chain output signal.Generally by using feedback signal to realize, feedback link is made of analog-digital converter and other required function for this.Self adaptation in the square frame 216,218 and 220 needs described feedback signal.

At square frame 216, according to transmit and feedback signal between residual error, revise one or more time domain compensation parameter vectors.For this reason, signal value preferably is fed.The signal value and the original data signal value that compare feedback signal, and, revise compensation parameter vector by changing coefficient according to the result.In a preferred embodiment, utilize polar coordinate system to carry out described modification.

At square frame 218, according to transmit and feedback signal between residual error, revise one or more frequency domain compensation parameter vectors.For this reason, signal value preferably is fed so that revise the compensating filter structure.Compare power amplifier signal value and original data signal value afterwards, and, determine the filter taps coefficient, thereby compensate frequency domain distortion better so that adjust filter according to the result.

At square frame 220, according to transmit and feedback signal between residual error, revise one or more quadrature modulator compensation parameter vectors.For this reason, signal value preferably is fed so that revise compensating parameter.Compare power amplifier signal value and original data signal value afterwards, and, determine the AQM compensation parameter vector, thereby compensate the AQM distortion better so that adjust the AQM compensation according to the result.

This method finishes in square frame 222.This process of arrow 224 graphic extensions can be an iteration.

Fig. 3 represents the flow chart of another preferred embodiment of the method for realization digital pre-distortion according to an embodiment of the invention.This embodiment of described method utilizes more filtration.Second filtration is used to compensate the frequency dependence that produces in down-conversion chain non-linear.Depend on system, also can utilize one or more filters or filter set to realize this filtration.This is preferably by the relatively signal value and the original data signal value of feedback signal, and determines that according to the result filter taps coefficient realizes.

This method starts from square frame 300.In square frame 302, form at least one time domain compensation parameter vector.Parameter vector can be considered to be made up of one or more subvectors, and each subvector is relevant with a nonlinear signal specific characteristic that causes power amplifier.In this application, vector also means the matrix type vector.

By providing its coefficient, parameter vector (function) is determined polynomial function, spline function or any other function.Batten can be characterized as being a function, and this function is to specify son multinomial at interval about every group in its territory.At son boundary at interval, batten is level and smooth equally.The time domain compensation parameter vector is used to the time domain predistortion.

Compare with the independent value of use, function (or vector) can be described the complex effects that is caused by non-linear better usually, and is main because of for the purpose of practicality, and the size of memory (use tracing table in the prior art) must be limited.Usually need several vectors, because the use of different vectors produces result more accurately.The number of the vector of selecting and vector itself depend on the typical radio electricity condition of system, and depend on required compensation precision naturally.Following four functions of general use: memoryless predistortion function, dynamically predistortion function, the dynamic predistortion function of weighted integral and the dynamic predistortion function of cross term.Difference between these functions can be interpreted into as described below.Memoryless predistortion function uses the range value of sampling.Dynamically the predistortion function also utilizes previous range value, so can predict the following direction that changes better.Integration predistortion function uses the review time cycle longer than dynamic predistortion function.By utilizing longer cycle review time, can follow the tracks of in the response of non-linear equipment, owing to the change of variations in temperature.The dynamic predistortion function of cross term utilizes memoryless function, kinematic function and integral function.It generally multiplies each other the value of these function definitions.In other words, by the output of making up other piece, form the cross term function according to suitable mode.

At square frame 304, form at least one frequency domain parameter vector (perhaps function).In theory, by transmission signals being used the inverse of nonlinear transfer function, can eliminate the infringement that causes by non-linear.But in fact, except the time domain error, always there is the frequency domain error, thereby also needs the frequency domain predistortion.Preferably by analyzing the frequency response of the definite signal of institute, and according to the results modification reverse filtration, formation frequency compensation parameter vector.

At square frame 306, form at least one quadrature modulator compensation parameter vector.At AQM (analogue quadrature moducator) and in AQDeMod (analog quadrature demodulator) compensation, the real part and the imaginary part of complex signal are adjusted, so that the error minimize that quadrature modulation or quadrature demodulation cause.General by in the predetermined sample of I (equally) and Q (quadrature) modulation signal, adding correction term, realize this compensation.General by the same historical information of using, obtain correction term from current I and Q sample.Usually (its independent variable is current and I in the past and Q sample (AQM state expander vector) and the previous AQM compensating parameter of determining, the calculation correction item according to predetermined function.In typical the realization, current and I in the past and Q sample and the function of the previous AQM compensating parameter of determining and the element linear correlation of predistorter coefficient and AQM state expander vector.For the calculating of correction term, also there are many other possibilities.For example, can use more complicated structure, wherein correction term is not linear depends on described parameter, but depends on described parameter with a kind of more complicated form.

At square frame 308, determine the nonlinear at least one group of characteristics of signals in the analogue transmission chain.In general, the character of the signal of use comprises amplitude, phase place or frequency.In many cases, one group of characteristics of signals is just enough, but sometimes in order to provide result more accurately, may need more groups.The non-linear of chain simulated, so that determine to form the parameter of state spread vector in square frame 310.

At square frame 310,, form at least one state spread vector according at least one group of characteristics of signals.The state spread vector is made up of the value that with non-linear sign is the function of the characteristics of signals selected.For example, the state spread vector can be by being arranged in vector, and the not homogeneous power of the predetermined number of range value forms.Another example is that the state spread vector is made up of the power of the time-derivative of the amplitude of predetermined number.Another example is the state spread vector by according to different modes: by difference, the range value that integration etc. are handled forms.The range value of handling according to different modes also capable of being combined.So the state spread vector can be by one or more range values, one or more derivative range values, one or more integration range values and/or the combined value that can be called as cross term constitute.

The number of variations of the item of the required type in the state spread vector: only use a kind of (for example amplitude) can obtain good result sometimes, but, may need more eurypalynous for more complicated situation.The length of state spread vector depends on the requirement of predistortion.In other words, Xiang number depends on the required quality of predistortion.Sometimes, use short vector can obtain good result, but for more complicated situation, the length of vector can be increased.

At square frame 312, utilize at least one time domain compensation parameter vector, utilize at least one frequency domain compensation parameter vector and at least one AQM compensation parameter vector to revise the characterization value, thereby form pre-distorted signals.Time domain is revised generally and to be characterized the selection parameter that value multiply by one or more time domain compensation parameter vectors by the prearranged signals with one or more state spread vector and realize.In general, the value that is multiplied each other is amplitude and/or phase parameter.In a preferred embodiment of the invention, in polar coordinate system, carry out the time domain predistortion.After time domain compensation, the parameter of compensation is combined so that obtain a value of each parameter, for example each raw value phase value and a range value.

Generally characterize the selection parameter that value multiply by one or more AQM compensation parameter vectors and realize the AQM compensation by prearranged signals with one or more AQM state spread vector.In a preferred embodiment of the invention, in cartesian coordinate system, realize the AQM compensation.

At square frame 314, form the feedback signal of chain output signal.The linearisation output signal of chain is fed, so that revise the predistortion function in time domain and frequency domain.Described modification is at time, frequency, amplitude and/or the phase variance of chain.Best following formation feedback signal in the practice: linearizing RF output signal is offered the down-conversion part, so that obtain intermediate-freuqncy signal.Subsequently described intermediate-freuqncy signal is offered analog-digital converter (ADC), at analog-digital converter (ADC), intermediate-freuqncy signal is sampled and converts to digital signal, and described digital signal is carried out demodulation (for example IQ demodulation).This digital signal (generally being complex digital signal) is provided for the self adaptation routine subsequently, in described self adaptation routine, and more described complex digital signal and corresponding original composite input signal.

At square frame 316, filter feedback signal, so that the non-linear of the frequency response that down-conversion chain causes minimizes.Its objective is the self adaptation of improving time domain compensation parameter vector and frequency domain compensation parameter vector.

At square frame 318, one or more time domain compensation parameter vectors are modified.For this reason, signal value preferably is fed.Signal value and corresponding original data signal value after the comparison down-conversion.By according to comparative result, change parameter vector and revise the predistortion function.

At square frame 320, according to transmit and feedback signal between residual error, revise one or more frequency domain compensation parameter vectors.For this reason, signal value preferably is fed so that revise the compensating filter structure.Compare down-conversion signal value and corresponding original data signal value afterwards.According to the result, determine the filter taps coefficient, thereby compensate frequency domain distortion better so that adjust filter.

At square frame 322, according to transmit and feedback signal between residual error, revise one or more quadrature modulator compensation parameter vectors.For this reason, signal value preferably is fed so that revise the compensating filter structure.Compare power amplifier signal value and original data signal value afterwards, and, determine the AQM compensation parameter vector, thereby compensate the AQM distortion better so that adjust the AQM compensation according to the result.

At square frame 324, be similar to frequency domain compensation vector self adaptation, revise the coefficient of feedback filter.

This method finishes in square frame 326.This method of arrow 328 graphic extensions can be an iteration.

The block diagram of the part of Fig. 4 graphic extension reflector according to an embodiment of the invention.Fig. 4 has mainly represented can realize by it various piece of the reflector of above-mentioned predistortion (perhaps preemphasis) method.For a person skilled in the art, emitter structures obviously can be different from the emitter structures of describing among Fig. 4.Square frame 400 is to check for example transmitting power, and frequency or bandwidth are so that be that different power level, frequency or bandwidth selected the suitable predistortion vector and/or the switching matrix of coefficient.Among Fig. 4, each different group vectors are by numeral 402,404,406,424,428,430 marks.The group number can change.

Square frame 402 is processing signals so that realize the state expander of appropriate predistortion.The state spread vector is by the value that with non-linear sign is the function of the characteristics of signals selected.For example, the state spread vector is made up of the not homogeneous power of the predetermined number of the one or more range values that are arranged in vector.Another example is that the state spread vector is made up of the not homogeneous power of the predetermined number of the amplitude of the sample that postpones predetermined number.Another example is the state spread vector by according to different modes: by difference, the range value that integration etc. are handled forms.The range value of handling according to different modes also capable of being combined.So the state spread vector can be by one or more powers of range value, one or more powers of the derivative of range value, one or more integration range values and/or the combined value that can be called as cross term constitute.

The state expander can be by about each input value, and for example the range value filter and the unit that produce the value of predetermined number formed.The state expander can expand to a semaphore value of predetermined number.If this structure comprises filter, they generally are finite impulse response (FIR) (FIR) or infinite impulse response (IIR) filter so.The output of state expander is to comprise that the requisite number purpose characterizes the vector of the value of the signal of wanting distortion.

The number of variations of required state spread vector: only use a vector can obtain good result sometimes, but, may need more vector for more complicated situation.The length of state spread vector depends on the requirement of predistortion.In other words, Xiang number depends on the required quality of predistortion.Sometimes, use short vector can obtain good result, but for more complicated situation, the length of vector can be increased.

Also different state spread vector can be used for different tranmitting frequencies, power, bandwidth and/or other chain variable, as shown in the equipment among Fig. 4 426.

Square frame 404,422 is described and is used for different transmit power level, transmission bandwidth, the time domain components for predistortion of other character of tranmitting frequency or chain.

Utilize one or more time domain compensation vectors to realize the time domain predistortion.In this application, term " vector " also comprises the matrix type vector.Vector also can be represented the coefficient of multinomial or batten.Understand the time domain compensation vector above in more detail.

Square frame 406,424 is described again and is used for different transmit power level, transmission bandwidth, the frequency domain components for predistortion of other character of tranmitting frequency or chain.Utilize one or more frequency domain compensation parameter vectors to realize the frequency domain predistortion.The frequency response of frequency domain vector compensation chain non-linear.The frequency domain predistortion can be realized as filter, and its frequency response is predefined for and chain mirror image relatively.In general, the behavior and the character of state expander control frequency domain predistortion.In this case, the parameter of compensation vector is a tap coefficient, and the length of vector is determined by the length of filter.Also understand the frequency domain compensation vector above in more detail.

Square frame 408 is realized number-Mo (D/A) conversion.The D/A conversion is known in the art, so no longer describe in detail here.

Square frame 410 is realized the analog functuion of reflector, such as up-conversion, down-conversion and power amplification.These functions are known in the art, so no longer illustrate in greater detail.An example of up-conversion and down-conversion is analogue quadrature moducator and demodulator.

In general, analogue quadrature moducator comprises the summing circuit of two frequency mixers and a combination frequency mixer output.Frequency mixer input be carrying base band homophase (I) signal and quadrature (Q) signal information and with the cosine part of the local oscillator signals of in-phase input signals for 1 mixing and with the positive string section of the local oscillator signals of quadrature input mixing.Quadrature demodulator is worked according to the mode opposite with quadrature modulator.The quality of analogue quadrature moducator and the influential emission spectrum of demodulation utensil and the various defectives of time domain linear.In addition, these realizations can reduce or even eliminate and to make the linearizing benefit of predistorter, thereby need compensation.So, carry out described compensation.

The following describes the feedback fraction of reflector.The main purpose of feedback link provides the information of revising the predistortion vector.Revising the predistortion vector is because distortion changed along with the time.

Square frame 412 is mould-number (A/D) transducers.The A/D conversion is known in the art, so no longer illustrate in greater detail here.

Square frame 414 is adaptive filtering device or filter set.If in feedback path, have many gains and phase fluctuation, so also can before the self adaptation routine, arrange an extra compensating filter in the output of down-conversion chain.This implementation structure and the similar of in the frequency domain predistortion, using.

Square frame 416 is to make primary data sample and be used to revise compensation vector, also is used to revise the correct feedback samples data in synchronization synchronization section of filter in addition if desired.Answer the feedback processing of attention to need the time, thereby the primary signal sample can resemble and is delayed the feedback signal value.

The similar of the structure of the second state expander 420 and the first state expander 402.This state expander vector by with predistortion in the corresponding or similar characterization value of the first state expander that uses form.By contrasting the residual signal in this state expander vector analysis feedback signal, can adjust the time domain compensation parameter vector so that obtain more performance.

Square frame 418 is to revise time domain components for predistortion 404,422, the self-adaptive component of frequency domain components for predistortion 406,424 and AQM compensating unit 428,430 (if necessary).In addition, feedback compensation filter 414 also is modified in this square frame.Because therefore the time variability of non-linear equipment needs this modification.By the coefficient of adjustment compensation vector or the tap coefficient of filter, iteration is carried out described self adaptation, so that find out the possibility correspondence of the best of chain transfer function.This is by estimating the self adaptation of the residual signal between primary signal and the feedback signal, be calculated as the error that elimination is considered subsequently that the variation of required coefficient aspect realizes.In a preferred embodiment, when beginning the self adaptation of time domain compensation parameter vector, calculate residual error about phase place and amplitude independently.For the frequency domain compensation parameter vector, feedback compensation filter and AQM compensation parameter vector are preferably in and calculate residual error in the cartesian coordinate system.

The adaptive process of time domain compensation parameter vector generally makes mean square deviation minimize.In the prior art, make the minimized method of mean square deviation have several.Here do not describe these methods in detail.Only mention several examples: LMMSE (linear least mean-square is poor), MMSE (Minimum Mean Square Error) or Kalman filter.Also can use other suitable method.

An adaptive purpose of frequency domain compensation vector is the frequency response linearityization that makes chain.The same procedure of using in time-domain adaptive can be used to frequency domain adaptive.

Utilization makes predetermined optimization criteria reach maximum algorithm according to feedback signal and primary signal, can find the AQM compensating parameter.In general, described optimization criteria is to make the negative value of the mean square deviation between primary signal and the one or more feedback signal reach maximum.If the use linear model in self adaptation, can use the LMS (lowest mean square) or RLS (recursive least square) algorithm of prior art so.

Square frame 428,430 is described the quadrature modulator compensation (AQM=analogue quadrature moducator) to other character of different transmit power level, transmission bandwidth, tranmitting frequency or chain.Utilize one or more compensation vector to carry out the quadrature modulator compensation.In this application, term " vector " also can comprise the matrix type vector.The front is understood the AQM compensation in more detail.

Also can realize AQDeMod (analog quadrature demodulator) compensation, square frame 432.In essence, can utilize identical method compensation AQDeMod and AQM, but in different self adaptation circulations (round), compensate self adaptation independently usually: at first, carry out the AQM compensation, utilize residual error to carry out the AQDeMod compensation subsequently.In AQDeMod and AQM self adaptation, little frequency displacement can be added in the feedback in addition, thus the linearity error between separate modulator and the demodulator.

Fig. 5 is the block diagram of the graphic extension said method transceiver that can be applied to.It will be obvious to those skilled in the art that transceiver also can comprise other parts except that shown in Fig. 5.

Digital Signal Processing square frame 500 is represented as in reflector the parts of the transceiver that forms user speech or data and need.Signal or by symbol, a string information that promptly one or more bits are formed is processed according to different modes in reflector.Comprise that for example the signal processing of coding/decoding and encrypt/decrypt is carried out usually in digital signal processor (DSP).If carry out transmission in the system with the form of frame (it is made up of time slot), so described frame generally forms in DSP, and in DSP interleaved symbol.Even signal encoding and the purpose that interweaves are to guarantee that all information bits can not be received, the information of emission also can be resumed in receiver.Digital Signal Processing (DSP) parts are shared by receiver and reflector.On the other hand, can be receiver and reflector independently DSP parts are provided respectively.

In reflector, in square frame 502, data-signal is by required modulator approach modulation.Modulator approach is known in the art, so no longer describe them here in detail.In the example shown in Fig. 5, data modulator 502 is realized modulator approach, and wherein signal is divided into homophase (I) component and quadrature (Q) component.An example of this modulator approach is Quadrature Phase Shift Keying (QPSK) and modification thereof, for example is offset the QPSK method.

Because the system among Fig. 5 is a broadband system, therefore, expand described signal for example by with the pseudo noise code of signal times with length.An example of such broadband system is UMTS.In square frame 504, realize expansion.If system is a narrowband systems, do not need widening parts so.

The modulation of in square frame 506, carrying out with for example wherein organize the multicarrier system of different carrier waves relevant at frequency domain according to being suitable for mode of the present invention.Can utilize the modulation in the existing method realization square frame 506.In Fig. 5, for the sake of clarity, a carrier wave has only been described.

In a preferred embodiment of the invention, independently carrying out predistortion and/or self adaptation in the predistortion DSP parts 508.For the sake of clarity, the required feedback link of not shown self adaptation among Fig. 5.

In square frame 510, signal is converted into analog form from digital form.RF parts 512 or directly perhaps by at first this signal being upconverted to intermediate frequency, amplify afterwards and filter this signal (if desired), this signal are upconverted to the tranmitting frequency of selection.Antenna 514 can be single antenna or the array antenna be made up of several antenna elements.If reflector and receiver use identical antenna, need duplexing filter to separate the so signal that will launch and the signal that will receive.

In receiver, in square frame 518, the signal of reception is by down-conversion, and this is the reverse operating of up-conversion.In square frame 520, the signal from analog form is converted into digital form subsequently.

Subsequently, in square frame 522, signal is by demodulation.The demodulation of carrying out in square frame 522 is with wherein must to separate the multicarrier system of different carrier waves in frequency domain in the mode of the system that is suitable for using at present relevant.Can realize demodulation in the square frame 522 according to existing mode.In Fig. 5, for the sake of clarity, a carrier wave has only been described.

If system is a broadband system, the signal of Jie Shouing is need be transformed into narrow band signal so that the further broadband signal of handling so.For example, this signal is gone expansion in expansion process by it is multiplied each other with the identical long pseudo noise code of using.

Subsequently, in square frame 526, this signal is by demodulation.This demodulation is called as data demodulates sometimes.Demodulation method is also known in the art, so no longer describe them here in detail.A purpose of demodulation is to eliminate the modulation of carrying out in reflector.

Advantageously, the disclosed function of the embodiment of the data transmission method of description can be realized by the software that generally is arranged in digital signal processor.Implementation also can be ASIC (application-specific integrated circuit (ASIC)) assembly for example.These different mixtures of realizing also are feasible.

Though about an example the present invention has been described with reference to the accompanying drawings above, but obviously the present invention is not limited thereto, in the scope of accessory claim, can revise the present invention on the contrary according to several modes.

Claims

1. A data transmission method for compensating for the nonlinearity of a transmission chain, said method comprising:

First, at least one time-domain compensation parameter vector is formed (202);

Next, forming (204) at least one frequency domain compensation parameter vector;

determining (208) at least one set of signal characteristics for simulating non-linearities in the transmission chain;

Third, from said at least one set of signal characteristics, forming (210) at least one state extension vector comprising magnitudes characterizing the signal;

Using said at least one time domain compensation parameter vector and said at least one frequency domain compensation parameter vector, modifying (212) the signal representative quantity of at least one state extension vector, thereby forming a predistortion signal;

Fourth, forming (214) a feedback signal based on the output signal of the transmission chain;

First, adapting (216) said at least one time-domain compensation parameter vector based on a residual error between a transmit signal and a feedback signal; and

Second, said at least one frequency domain compensation parameter vector is adapted (218) based on said residual error between the transmitted signal and the feedback signal.

2. A method of data transmission that compensates for the nonlinearity of a transmission chain, said method comprising:

First, at least one time-domain compensation parameter vector is formed (203);

Next, forming (304) at least one frequency domain compensation parameter vector;

determining (308) at least one set of signal characteristics for simulating non-linearities in the transmission chain;

Third, based on said at least one set of signal characteristics, forming (310) at least one state extension vector comprising magnitudes characterizing the signal;

modifying (312) the signal characterization magnitude of at least one state extension vector using said at least one time domain compensation parameter vector and said at least one frequency domain compensation parameter vector, thereby forming a predistortion signal;

Fourth, forming (314) a feedback signal based on the output signal of the transmission chain;

filtering (316) the feedback signal to minimize the nonlinear frequency response of the feedback chain;

First, said at least one time-domain compensation parameter vector is adapted (318) according to a residual error between a transmit signal and a feedback signal;

Second, adapting (320) said at least one frequency domain compensation parameter vector based on said residual error between a transmit signal and a feedback signal; and

Third, at least one compensation parameter vector of the feedback filter is adapted (324) based on a residual error between the transmit signal and the feedback signal.

3. A method of data transmission that compensates for the nonlinearity of a transmission chain, said method comprising:

First, at least one time-domain compensation parameter vector is formed (202);

Third, forming (206) at least one quadrature modulator compensation parameter vector;

Fourth, from said at least one set of signal characteristics, forming (210) at least one state extension vector comprising magnitudes characterizing the signal;

Using the at least one time-domain compensation parameter vector, the at least one frequency-domain compensation parameter vector, and the at least one quadrature modulator compensation parameter vector, modify (212) the signal characterization value of at least one state extension vector to form predistortion signal;

Fifth, forming (214) a feedback signal based on the output signal of the transmission chain;

First, said at least one time-domain compensation parameter vector is adapted (216) according to a residual error between a transmit signal and a feedback signal;

Second, adapting (218) said at least one frequency domain compensation parameter vector based on said residual error between a transmit signal and a feedback signal; and

Again, said at least one quadrature modulator compensation parameter vector is adapted (220) based on said residual error between the transmit signal and the feedback signal.

4. A method of data transmission that compensates for the nonlinearity of a transmission chain, said method comprising:

First, at least one time-domain compensation parameter vector is formed (302);

Third, forming (306) at least one quadrature modulator compensation parameter vector;

Fourth, from said at least one set of signal characteristics, forming (310) at least one state extension vector comprising magnitudes characterizing the signal;

Using the at least one time-domain compensation parameter vector, the at least one frequency-domain compensation parameter vector, and the at least one quadrature modulator compensation parameter vector, modify (312) the signal characterization value of at least one state extension vector to form predistortion signal;

Fifth, forming (314) a feedback signal based on the output signal of the transmission chain;

Second, adapting (320) said at least one frequency domain compensation parameter vector according to a residual error between the transmitted signal and the feedback signal;

Again, adapting (322) the at least one quadrature modulator compensation parameter vector based on a residual error between the transmit signal and the feedback signal; and

Finally, at least one compensation parameter vector of the feedback filter is adapted (324) based on the residual error between the transmitted signal and the feedback signal.

5. The method according to claim 3 or 4, wherein the first forming step further comprises selecting said at least one time domain compensation parameter vector based on at least one of transmit power, frequency, bandwidth and another transmission chain characteristic.

6. The method according to claim 3 or 4, wherein the second forming step further comprises selecting said at least one frequency domain compensation parameter vector based on at least one of transmit power, frequency, bandwidth and another transmission chain characteristic.

7. The method according to claim 3 or 4, wherein the third forming step further comprises selecting said at least one quadrature modulator compensation parameter according to at least one of transmit power, frequency, bandwidth and another transmission chain characteristic vector.

8. The method of claim 3 or 4, further comprising selecting the state expander function based on at least one of transmit power, frequency, bandwidth and another transmission chain characteristic.

9. The method according to claim 3 or 4, wherein said fourth forming step of forming at least one state extension vector further comprises the step of:

A function comprising at least one of a memoryless pre-emphasis function, a dynamic pre-emphasis function, a weighted integral dynamic pre-emphasis function, and a cross-term dynamic pre-emphasis function.

10. A method according to claim 3 or 4, wherein said first adapting step further comprises the step of:

The compensation parameters of the at least one compensation parameter vector are configured according to the residual error between the transmit signal and the feedback signal.

11. The method according to claim 3 or 4, wherein said second adapting step further comprises the step of:

12. The method according to claim 3 or 4, wherein said third adapting step further comprises the step of:

13. The method of claim 3 or 4, wherein said first forming step further comprises the step of:

At least one time-domain compensation parameter vector is searched for a predetermined signal characteristic.

14. The method of claim 3 or 4, wherein said second forming step further comprises the step of:

At least one frequency domain compensation parameter vector is searched for a predetermined signal characteristic.

15. The method of claim 3 or 4, wherein said third forming step further comprises the step of:

At least one quadrature modulator compensation parameter vector is searched for predetermined signal characteristics.

16. The method of claim 3 or 4, further comprising the step of:

Implement temporal predistortion in polar coordinates.

17. A method according to claim 3 or 4, further comprising the step of performing temporal predistortion,

The adaptation step also includes the steps of:

The at least one time domain compensation parameter vector is utilized in a polar coordinate system.

18. The method of claim 3 or 4, further comprising performing analog quadrature demodulator compensation.

19. The method of claim 3 or 4, further performing analog quadrature demodulator compensation and adaptation.

20. A transmitter that compensates for non-linearities of a transmission chain, said transmitter comprising:

first forming means for forming at least one time-domain compensation parameter vector;

second forming means for forming at least one frequency domain compensation parameter vector;

determining means for determining at least one set of signal characteristics for simulating non-linearities in the transmission chain;

From said at least one set of signal properties, forming third forming means comprising at least one state extension vector characterizing the magnitude of the signal;

Using the at least one time-domain compensation parameter vector and the at least one frequency-domain compensation parameter vector to modify the signal characteristic value of at least one state extension vector, thereby forming a modification device for a predistortion signal;

fourth forming means for forming a feedback signal from the output signal of the transmission chain;

First adapting means for adapting said at least one time-domain compensation parameter vector based on a residual error between the transmitted signal and the feedback signal; and

Second adaptation means for adapting said at least one frequency-domain compensation parameter vector based on a residual error between the transmitted signal and the feedback signal.

21. A transmitter for compensating for non-linearity of a transmission chain, said transmitter comprising:

Filter the feedback signal to minimize the nonlinear frequency response of the feedback chain;

first adapting means for adapting said at least one time-domain compensation parameter vector according to a residual error between the transmitted signal and the feedback signal;

second adapting means for adapting said at least one frequency domain compensation parameter vector according to a residual error between the transmitted signal and the feedback signal; and

Third adaptation means for adapting at least one compensation parameter vector of the feedback filter according to the residual error between the transmitted signal and the feedback signal.

22. A transmitter for compensating for non-linearities of a transmission chain, said transmitter comprising:

third forming means for forming at least one quadrature modulator compensation parameter vector;

From said at least one set of signal properties, forming fourth forming means comprising at least one state extension vector characterizing the magnitude of the signal;

Using the at least one time-domain compensation parameter vector, the at least one frequency-domain compensation parameter vector, and the at least one quadrature modulator compensation parameter vector, modify the signal characteristic value of at least one state extension vector, thereby forming a predistortion signal modification device;

fifth forming means for forming a feedback signal from the output signal of the transmission chain;

Third adaptation means for adapting said at least one quadrature modulator compensation parameter vector according to the residual error between the transmitted signal and the feedback signal.

23. A transmitter for compensating for non-linearity of a transmission chain, said transmitter comprising:

second adaptive means for adapting said at least one frequency domain compensation parameter vector according to the residual error between the transmitted signal and the feedback signal;

third adapting means for adapting said at least one quadrature modulator compensation parameter vector based on a residual error between the transmitted signal and the feedback signal; and

Fourth adaptation means for adapting at least one compensation parameter vector of the feedback filter according to the residual error between the transmitted signal and the feedback signal.

24. A transmitter according to claim 22 or 23, further comprising selection means for selecting said at least one time domain compensation parameter vector based on at least one of transmission power, frequency, bandwidth and another transmission chain characteristic.

25. The transmitter according to claim 22 or 23, further comprising selection means for selecting said at least one frequency domain compensation parameter vector based on at least one of transmission power, frequency, bandwidth and another transmission chain characteristic.

26. The transmitter according to claim 22 or 23, further comprising selection means for selecting said at least one quadrature modulator compensation parameter vector according to at least one of transmission power, frequency, bandwidth and another transmission chain characteristic .

27. A transmitter according to claim 22 or 23, further comprising selection means for selecting the state extender function based on at least one of transmission power, frequency, bandwidth and another transmission chain characteristic.

28. The transmitter according to claim 22 or 23, further comprising: by using at least one of a memoryless pre-emphasis function, a dynamic pre-emphasis function, a weighted integral dynamic pre-emphasis function and a cross-term dynamic pre-emphasis function function, a fourth forming means for forming at least one state extension vector.

29. A transmitter according to claim 22 or 23, further comprising first adapting means for adapting the compensation parameters of said at least one compensation parameter vector according to the residual error between the transmitted signal and the feedback signal.

30. A transmitter according to claim 22 or 23, further comprising second adapting means for adapting the compensation parameters of said at least one compensation parameter vector according to the residual error between the transmitted signal and the feedback signal.

31. A transmitter according to claim 22 or 23, further comprising third adapting means for adapting the compensation parameters of said at least one compensation parameter vector according to the residual error between the transmitted signal and the feedback signal.

32. A transmitter according to claim 22 or 23, further comprising searching said at least one time domain compensation parameter vector, said at least one frequency domain compensation parameter vector and said at least one quadrature modulator A search device for the compensation parameter vector.

33. A transmitter as claimed in claim 22 or 23, further comprising distortion means for effecting temporal predistortion in polar coordinates.

34. A transmitter according to claim 22 or 23, further comprising distortion means for implementing temporal predistortion, and fourth adapting means for adapting said at least one temporal compensation parameter vector in polar coordinates.

35. The transmitter according to claim 22 or 23, said fourth forming means for forming said at least one state extension vector further comprising: means for a function of at least one of an emphasis function and a cross-term dynamic pre-emphasis function.

36. A transmitter according to claim 22 or 23, further comprising third forming means for forming at least one quadrature modulator compensation parameter vector using at least one of the following parameters: transmit power, frequency or bandwidth.

37. A transmitter as claimed in claim 22 or 23, further comprising means for performing analog quadrature demodulator compensation.

38. A transmitter that compensates for non-linearities of a transmission chain, the transmitter configured to:

forming at least one time-domain compensation parameter vector;

forming at least one frequency domain compensation parameter vector;

forming at least one quadrature modulator compensation parameter vector;

determining at least one set of signal characteristics for simulating non-linearities in the transmission chain;

From said at least one set of signal characteristics, forming at least one state extension vector comprising magnitudes characterizing the signal;

Using the at least one time-domain compensation parameter vector, the at least one frequency-domain compensation parameter vector, and the at least one quadrature modulator compensation parameter vector, modify the signal characteristic value of at least one state extension vector, thereby forming a predistortion signal ;

forming a feedback signal from the output signal of the transmission chain;

adapting the at least one time-domain compensation parameter vector based on a residual error between the transmit signal and the feedback signal;

adapting the at least one frequency domain compensation parameter vector based on a residual error between the transmitted signal and the feedback signal; and

The at least one quadrature modulator compensation parameter vector is adapted based on a residual error between the transmit signal and the feedback signal.

39. A transmitter that compensates for non-linearities of a transmission chain, the transmitter configured to:

forming at least one time-domain compensation parameter vector;

forming at least one frequency domain compensation parameter vector;

Using the at least one time-domain compensation parameter vector and the at least one frequency-domain compensation parameter vector to modify the signal representation value of at least one state extension vector, thereby forming a predistortion signal;

forming a feedback signal from the output signal of the transmission chain;

At least one coefficient of the feedback filter is adapted based on the residual error between the transmit signal and the feedback signal.

40. A transmitter that compensates for non-linearities of a transmission chain, the transmitter configured to:

forming at least one time-domain compensation parameter vector;

forming at least one frequency domain compensation parameter vector;

forming at least one quadrature modulator compensation parameter vector;

Using the at least one time-domain compensation parameter vector, the at least one frequency-domain compensation parameter vector, and the at least one quadrature modulator compensation parameter vector, modify the signal characterization value of at least one state extension vector, thereby forming a predistortion signal ;

forming a feedback signal from the output signal of the transmission chain;

41. A transmitter that compensates for non-linearities of a transmission chain, the transmitter configured to:

forming at least one time-domain compensation parameter vector;

forming at least one frequency domain compensation parameter vector;

forming at least one quadrature modulator compensation parameter vector;

forming a feedback signal from the output signal of the transmission chain;

adapting the at least one frequency domain compensation parameter vector according to a residual error between the transmitted signal and the feedback signal;

adapting the at least one quadrature modulator compensation parameter vector based on a residual error between the transmit signal and the feedback signal; and

At least one coefficient of the feedback filter is adapted based on a residual error between the transmit signal and the feedback signal.

42. A base station, wherein non-linearity of a transmission chain is compensated, said base station comprising:

Using the at least one time-domain compensation parameter vector and the at least one frequency-domain compensation parameter vector to modify the signal characteristic value, thereby forming a modification device for a predistortion signal;

43. A base station, wherein non-linearity of a transmission chain is compensated, said base station comprising:

44. A base station, wherein non-linearity of a transmission chain is compensated, said base station comprising:

Using the at least one time domain compensation parameter vector and the at least one frequency domain compensation parameter vector to modify the signal characteristic value, thereby forming a modification device for the predistortion signal;

45. A base station, wherein non-linearity of a transmission chain is compensated, said base station comprising:

A filter that filters the feedback signal to minimize the nonlinear frequency response of the feedback chain;

Fourth adaptation means for adapting at least one coefficient of the feedback filter according to the residual error between the transmitted signal and the feedback signal.